for me N86 still better because it is a smartphone[Symbian]

while C905 better in camera IMHO...
but N86 has variable apertures , 3rd Generation LED flash , which i can say that their both performance about the same

C905 worse in video but better in camera,
N86 worse in camera . but better in video

it depends on what that you want..
both of them has pros and cons..

if you dont know how to handle a smartphone.. just forget N86.. go for C905

fr entertainment+biz+casual.. go for N86